I think the Question is more of Renée as a heroine than a cop. But her Detective Comics stories probably hit that mark well, not the main story though obviously.
I mean, Nightwing was a Blüdhaven police officer for most of his title (Vol 2), haha.
I’ve never really been into police stories in comics. The genre works better on television, for me.
I can think of dc.wikia.com/wiki/Hawkworld_Vol_1 (3 issue series) which is a police story on Thanagar.
Straight-up police story? dc.fandom.com/wiki/1st_Issue_Special_Vol_1_4 Lady Cop
EDIT: Also; Black Lightning: Cold Dead Hands features the police on their worst behaviour. And an old compilation book dc.wikia.com/wiki/DC_Special_Vol_1_10 is called: “Stop! You Can’t Beat the Law”
Fell by Warren Ellis
